package com.web.logindemo.aspectj;

import com.web.logindemo.common.annotation.DataSource;
import com.web.logindemo.common.util.StringUtils;
import com.web.logindemo.config.datasource.DynamicDataSourceContextHolder;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;

import java.util.Objects;

/**
 * 多数据源处理
 */
@Aspect
@Order(1)
@Component
public class DataSourceAspect {
    protected Logger log = LoggerFactory.getLogger(getClass());
    @Pointcut("@annotation(com.web.logindemo.common.annotation.DataSource)")
    public void dsPointCut(){

    }

    @Around("dsPointCut()")
    public Object around(ProceedingJoinPoint point) throws Throwable{
        DataSource dataSource = getDataSource(point);
        if(StringUtils.isNotNull(dataSource)){
            DynamicDataSourceContextHolder.setDataSourceType(dataSource.value().name());
        }

        try{
            return point.proceed();
        }finally {
            // 销毁数据源 在执行方法之后
            DynamicDataSourceContextHolder.clearDataSourceType();
        }
    }

    private DataSource getDataSource(ProceedingJoinPoint point) {
        MethodSignature signature = (MethodSignature) point.getSignature();
        DataSource dataSource = AnnotationUtils.findAnnotation(signature.getMethod(), DataSource.class);
        if(Objects.nonNull(dataSource)){
            return dataSource;
        }
        return AnnotationUtils.findAnnotation(signature.getDeclaringType(), DataSource.class);
    }
}
